Table II.

Presence of immune cells in the normal testis and epididymis of adult mouse and human.

Immune cells	Common markers	Testis		Epididymis
		Mousea	Human	Mouse	Human
Macrophages  M1 classically activated  M2 alternatively activated	CD68, F4/80 (mouse), CD11b CD86, MHC class II CD163, CD206	+++	+++	+	+
Dendritic cells	CD11c, CD209, MHC class II, CD80, CD86	+	(+)	++b	++
T cells	CD3, CD4, CD8, Foxp3	+	+	+	+
B cells	CD19, CD 20, B220 (CD45R)	+	(+)	+/−	?
Natural killer cells	CD56, CD161 (NK1.1)	+	(+)	?	?
Mast cells	Tryptase Fc epsilon RI alpha, CD117 (c-kit), CD23, CD203c	(+)	+	+	+

^aConcerning the overall occurrence of immune cell subpopulations, comparable results exist for the rat; ^btubular wall.

(+) Very few.

+++ Abundant.

MHC, major histocompatibility complex.